Hydraulic brake



Sept. l2, 1933. F E, FLADER 1,926,988

HYDRAULIC BRAKE Filed Oct. 19, 1951 2 Sheets-Sheet l gwvmdoi Hf ederz'Tf/adel;

Sept. 12, 1933.

E. FLADER n 1,926,988

HYDRAUL I C BRAKE Filed Oct. 19, 1931 2 Sheets-Sheet 2 Patented sept.172,r` 1933.

, regatas 'HYDRAULICl BRAKE Fredric E. Flader, ylflorrisville, Pa.,assigner of one-third to Fred Dobmeier,--uf`r`alo, N. Y;

Application October 19, 1931. Serial No. 569,809

' 7.o1aims.; (01.188-92) ferential portions of the` discs tocornpletethel n This invention relates to hydraulic brakes and it has particularrelation to the type of hydraulic brake in which the braking action isaccomplished by resistance to forced iiovv of fiuid through controlledopenings. The invention contemplates ahydraulic brake which isparticularly adapted to be employedin conjunctiongwith the undercarriageof vehicles, such as the landing equipment of aircraft, although theWheels of other types of vehicles are Asuitable for application of theinvention; The brake is so constructed that it is not necessary toemploy frictional braking surfaces and the rotation of the Wheelprovides the power for forcing uid through openings that are controlledat will by the vehicle operatorto such degree that thelwheels may evenbe locked. Other features of the invention include the installation ofthe operating parts of the brake Within the outline or boundaries of theWheel, thereby facilitating its streamlining, and onlyrelatively smallfluid conduits leading from the Wheel to'the'body of the vehicle arenecessary forthe actuation. of the brake. A suitable supply of liquid islocated upon the body of the vehicle. This fluid supply may be intheforni of a tank or shockV absorbers on the vehicle undercarriage.

no appreciable Wind resistance is offered by' the installation thereofbecause it is locatedwithin the boundaries of other vehicle elements. e

For a better understanding ofthe linvention reference may now be had tothel accompanying drawings forming a part which Y Y Y n Fig. l is afragmentary elevation of a hydraulic brake, an axle Yand wheel Withwhich it is associated being shown incross-section;

Fig. 2 is a cross-section taken 'substantially et()v alongthe line II`IIof Fig. .1; and y Fig. -3 is a fragmentary cross section taken sub-` astantially along the line III-III of Fig. 1.

In practicing the invention a tubular metallic axle -l0 is providedwhich constitutes a stationary portion ofr a landing gearorundercarriage` of an aircraft 'or other vehicle.` A disc wheel` 12mounted on the axle comprises a pair' of spaced discs 13 and 14 andcentral bearing housings 16 and 17 that are rigidly secured as indicatedat 18,

to the discs and are provided with roller bearing members 19 upon theaxle; bers Yare Ypositioned and maintained in `their proper relationlwith respect to the inner portion 'of the axle by means of vanannular'shoulder'ZO and with respect to the outer end of the `axle bymeans lof nuts 227. Packingrings 23 having pack-V ing material 24therein surround the axle in the bearing housing and serve to protectthe bear-.

ing members.` A tire carrying rim 26is rigidly secured, as indicated at27, to the outer circum- The streamlining of the! vehicle is notladversely affected by the brake, `and of thisspecication, of

provided with a screw threaded portion 56. gear 57 rigidly secured tothe'shaft 36 inthe These bearing mein'- Y Wheel assembly. s

vAs best shown by Fig. 2 a beveled gear 30 sur-Q .rounding the axle issecured by means of rnachine screws 32, or the likatothe inner face ofthe bearing housing 16 and accordingly is'rctatable with the Wheel aboutthe vstationary axle;` Diametrically opposite, beveled gears 34meshingWith'thev gear 3G are rigidly secured to Ythe inner ends 'of shafts 36that are disposed radially with respect to the axle 10 and are mountedin bearingy bosses 37 on a casting 38 located Within the disc Wheel. Acentral'portion ofthe casting surroundsthe axle and provides a bearing35 against which the housing 17 abuts in opposed relation to the gear30. Relatively short bolts 39 screw threaded through bosses 40 that areinteY gralvvith kthe casting are provided with dowel end portion 42projecting'through.openings 43 in. diametrically opposite sides of thetubular axley and slightlybeyondthe inner Wall surfacesV ofthe latter.

` Suitable gland `packing vle and a gland nut'`A threaded into thebearing boss 37 provideV a fluid tight` bearing connection for eachshaft 36. These shafts constitute the principal elements of iluid pumps47 which are identical in construction and accordingly a detaileddescription of one ofA them Will'` adequately suflice` for a thoroughunderstanding of both.

The portion of the casting in which the bearing boss 37 is located is inthe form of an integral` plate 48 for receiving a fianged housing r50'rigidly bolted thereto, as indicated at 52. A thrust bear'- ing 53 inthe outer end of the housing receives an outerend portion 54 of theshafteand. an intere mediate portion of the shaft inr the housing is Ainner end portion of the housing 50 is spaced from the bearing member 37by means of a Washer 58 and intermeshes With a similar gear 59 that isrigidly secured to a shaft 60 having bearings 62 and 63 at its oppositeends in the housingV 50 and plate 48 respectively. An intermediateportion of the shaft 60 is in the form of screw threads 6a intermeshingWith the threads 55 of the shaft tions 56 and 641 are reverselyv formed,that is,'one of 'them is in the form of right hand threads and the otherin the form of left hand threads. The diameters of the threaded portionsof the shaft is slightly greater than the diameters of the end portionthereof and substantially fluid `tight chambers 66 and 67 are thusprovided beyond the opposite ends of the. threaded portions of theshafts. The housing 50 fitsl snugly about the screw threaded portions ofthe shafts 36 and 60.

A'hollow conduit joint fitting 63 having a tapered portion 69 threadedtightly into an inloo lty will `be observed that the threaded por- Yduit 78 with a fluid supplying device 80, such as an oil tank or shockabsorber which is illustrated diagrammatically in Fig. 2.

In like manner the upper or outer chamber 67 is'provided with a taperedopening 82 in which a conduit fitting 83 is secured in threaded relationfor communication with the fiuid supplying device 8G by means of aconduiti, tubular fitting 86, an angular duct 87 in the plug'ei, and aconduit S3 secured in the plug '74. A valve 90 in the conduit 88 isprovided with an actuating member 92 that is accessible to the operatorofthe vehicle or aircraft upon which the brake isinstallecl for thepurpose of controlling or regulating` Athe flow of fluid therethrough. l

In the operation of the brake described the fluid supply device 80 isfilled with suitable iiuid such as oil which circulates through thevarious conduits described into the chambers 6-3 and 6?. As soon as thewheel l2 begins to rotate upon the ground the threaded shafts 35 and 50are rotated by means of the gears 30 and 34, and the inter-meshingthreaded portions 56 and 54 thereof pump oil from the chamber into thechamber 67. The amount of resistance offered by the n flow of pump fiuiddepends upon the rapidity of the rotation of the wheel and also upon theamount of fiuid that is permitted to pass through the valve 9G. When thevalve is open the resistance is relatively small and thus the resistancecan be graduated by gradually opening and ciosing the valve. If thevalve is closed a very strong resistance is offered which will lock rtheWheel against rotation, assuming that there is no fluid leakagev in thesystem. Y f

From the foregoing description it will be apparent that a very positiveand emcient braking construction 'nas been provided which avoids thewear and tear ordinarily incurred in using brakes having frictionalsurfaces. This type of brake does not interfere in any manner With'thestreamlining of an aircraft and in View of the fact that thewheels areonly ,rotated at intervals When thecraft is at the ground the brakingelements are subjected to relatively slight wear and tear.

'Although only one form of the invention has been shown and described indetail it Will be apparent to those skilled in the art that theinvention is not so limited but that various changes maybe made Withoutdeparting from the spiritv of the invention or from thescope of theappended claims. Further, any suitable type of pump may be substitutedfor the screw type shown.

I claim: Y n

1. The combination with a wheel having cooperating discs'for supportinga tire rim and an axle rigidly supporting the discs, of a fluid pumpmounted'within the wheel donned by the discs, means for supplying fluidto the pump, one of said discs having driving means for actuating thepump as the Wheel is rotated about the axle, and means for restricting-theiiow of uid through the pump to provide a braking action resistingthe rotation of the wheel.

2. The combination With a Wheel having cooperating discs for supportinga tire rim and an axie therefor, of a stationary vsupport on the axlebetween `the disc, said support having a thrust bearing for bearingagainst onel of the discs a duid pump mounted upon said support Withinthe Wheel defined by the discs, means for supplying fluid to the pump,gearing on the disc opposite the thrust bearing for {inter-connecting*the wheel and the pump and for actuating the pump when the Wheel isrotated about the axle, and means for restricting the flow of fiuidthrough the pump to provide a braking action resisting the rotation ofthe Wheel.

3. The combination with a wheel and an axle rotatablyvmounted thereon,of a casting mounted upon the axle and including oppositely disposedplate like portions, a pair of pumps mount- 'ed upon the plate likeportions of the casing,

means for supplying iiuid to the pumps, common bevel gearing on arotating part of the wheel for operating the pumps when the Wheel isrotated about the'axle, and means for restricting the iiow of fiuid fromthe pumpto provide a braking action resisting the rotation `of theWheel.

i. vThe combination with a Wheel and anv axle, bearing members rotatablysupporting the Wheel on the axle, a gear on one of the bearing members,symmetrically arranged fluid pumps, sup-- operating the pump when theWheel is rotated, 1

the axis ofthe pump being disposed transversely lofthe axis 'of theaxle, a closed fiuid supply system communicating AWith the pump, meansfor controlling the flow of fluid through the pump as the Wheel isrotated to provide a gradual variation in ,braking action against therotation of the wheel.

6. The combination with an axle andra Wheel rotatably mounted thereon,of a pump mounted upon the support, means on the wheels for operatingthe pump, a closed fluid supply system communicating With the pump, saidsupply system` including an apertured plug mounted axially in the axle,common means for securing said support' and plug rigidly With respect tothe axle, avalve in the system for controlling the flow of fluid fromthe pump, and means for actuating the valve yas the Wheel rotates toprovide varying braking action against the rotation of the wheel;

rI. The combination with an axle and Wheel rotatably mounted thereon, ofa casting having a central portion surrounding the axle, symmetricalpumps mounted upon the casting, gearing interconnecting the Wheel andpumps, a closed fluid supply system communicating` With the pump, saidsupply system including common conduits communicating with the suctionand pres-v sure sides ofthe pumps, an apertured plug in` eluded in thesystem and mounted axially of the axle, common means for securing theplug and casting rigidly upon the axle, a valve common to both pumps forcontrolling the flow of fluid from the pumps to provide a braking actionagainst rotation of the Wheel.

FREDRIC E. FLADER.

